Paper 2012/256

The myth of generic DPA...and the magic of learning

Carolyn Whitnall, Elisabeth Oswald, and François-Xavier Standaert

Abstract

A generic DPA strategy is one which is able to recover secret information from physically observable device leakage without any a priori knowledge about the device's leakage characteristics. Here we provide much-needed clarification on results emerging from the existing literature, demonstrating precisely that such methods (strictly defined) are inherently restricted to a very limited selection of target functions. Continuing to search related techniques for a `silver bullet' generic attack appears a bootless errand. However, we find that a minor relaxation of the strict definition---the incorporation of some minimal non-device-specific intuition---produces scope for generic-emulating strategies, able to succeed against a far wider range of targets. We present stepwise regression as an example of such, and demonstrate its effectiveness in a variety of scenarios. We also give some evidence that its practical performance matches that of `best bit' DoM attacks which we take as further indication for the necessity of performing profiled attacks in the context of device evaluations.

Note: Revised to match author version of the article as published in the proceedings of CT-RSA 2014.